Question to the Department for Work and Pensions:

To ask the Secretary of State for Work and Pensions, what recent estimate his Department has made of the (a) number of gas jobs conducted annually by unqualified workers and (b) the proportion assessed as unsafe; and what proportion of unsafe gas works are linked to carbon monoxide leaks.

The Health and Safety Executive (HSE) is responsible for the Gas Safety (Installation and Use) Regulations 1998 (GSIUR) which address the safe installation, maintenance, and use of gas systems, in commercial and domestic premises.  Under GSIUR, gas engineering businesses must be registered with the Gas Safe Register (GSR) to carry out work covered by the Regulations legally. GSR runs the approved registration scheme for gas engineers on behalf of HSE and, as part of its remit, it ensures that all registered engineers have the appropriate qualifications to conduct gas work, and it conducts investigations into illegal gas work.

HSE has not made an estimate of the number of gas jobs conducted annually by unqualified workers, but it does have statistics for HSE enforcement notices for work carried out by unregistered gas fitters and GSR investigations into unregistered gas work.

In 2024/2025, 522 site investigations were carried out into unregistered gas work and those investigations identified 4548 immediately dangerous, at risk or not to current standard defects which were attributed to unregistered fitters. HSE issued 44 prohibition notices in relation to unregistered gas work against 42 businesses.

HSE is unable to provide figures for the proportion of unsafe gas works that were linked to carbon monoxide.